Passenger restraint systems for the rear seat of a vehicle which incorporate an air bag and gas generator have been proposed previously in the prior art. The known passenger restraint systems equipped with an air bag and a gas generator are generally installed in the region of the outer edge of the seat back. The air bag module, consisting of the air bag and gas generator, is covered on the outside with upholstery material for the seat back. The upholstery material covering is provided with a tear-seam that forms a weak spot at the point where the air bag is intended to emerge during deployment. In practice, it has been shown that the deployment force required for the air bag to penetrate the upholstery covering at the tear-seam varies greatly. The effects of this variation can include a negative effect on the desired deployment speed with which the air bag emerges.
Published Japanese Patent Abstract JP 4-166451 discloses another air bag equipped passenger restraint system in which the air bag module is installed in the rear side door as protection for the rear seated passengers in the event of a lateral impact. The air bag module is disposed within the rear side door and is covered by a padded flap. The padded flap includes a weakened point designed as a breaking point for the emergence of the air bag upon deployment. Here again, the breaking point of the padded flap covering cannot be easily controlled. In addition, the violent tearing of the padded flap covering caused by the strong inflation force of the air bag may form undesirable sharp-edged burrs along the breaking point which could puncture the air bag.